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We obtained a complete census of vegetation in a 30- x 1,900-m plot in the Sonoran Desert (Tumamoc Hill, Pima County, Ariz.). We then evaluated the accuracy of 5 sampling techniques commonly used to sample vegetation in deserts: step-point, point-quarter, and 3 line-intercept methods, We compared presence and percent occurrence for each method with the census, The line-intercept (method 3) most closely estimated the census: it was closer for all species occurring on >1% of the site, revealed the least variability relative to sample size for dominant species, and accounted for more (20 of 23) plant species on the study site than the other methods.